I Never Knew Before: Why Doraemon is Blue

When I first heard the reason why Doraemon is blue yesterday, that he was originally yellow like his sister, Dorami, I thought it was complete BS, told to me by someone who usually is full of BS.

A check with wikipedia reveals:

Doraemon's original paint color was yellow. After getting his ears gnawed off by the robot mouse, he slipped into depression on top of a tower, where he drank a potion with a label having letters that resembled "sadness". As he cried for a long time, the yellow color washed off and his voice changed due to the potion.

Now that explains why the cat doesn't have ears.....